TORONTO, Feb 24 (Reuters) - Toronto's main stock index closed lower for a fourth straight session on Thursday as energy and gold-mining issues retreated after rising for several days in reaction to the upheavals in North Africa.

The energy group, which had advanced more than 8 percent with gains in eight of the previous nine sessions, fell 1.88 percent. Suncor Energy (SU.TO) slumped 4.51 percent to C$44.00, while Canadian Natural Resources (CNQ.TO) shed 2.2 percent to C$47.06.

Oil prices skidded after rallying to 2-1/2-year highs, with traders citing a rumor that Libyan leader Muammar Gaddafi had been shot as one reason for the late selloff. [O/R] [ID:nL3E7DO0SC

"The energy (sector) really seems to be taking a hit here, but it has had a very good gain," said John Kinsey, a portfolio manager at Caldwell Securities Ltd.

Violence in Libya, and worries the crisis could spread to other oil-producing countries in the Middle East, had sent crude prices soaring over the last several sessions. [ID:nLDE71N009]

Gold miners were also in heavy retreat and helped drag the overall materials group 2.2 percent lower.